One main disadvantage of MIMO-OFDM is that the signals transmitted on different antennas might exhibit a prohibitively large peak-to-average power ratio (PAPR). Peak-to-average power ratio (PAPR) reduction schemes have been proposed for orthogonal frequency division multiplexing (OFDM) systems. Among them, signal scrambling methods are attractive since OFDM signals are modified without distortion to present better PAPR properties with a relatively low complexity. In MIMO-OFDM systems it would appear that a straightforward way for PAPR reduction would be to apply existing schemes proposed for OFDM systems separately on each transmit antenna.